Recently, there has been a raised awareness of environmental concern, and a technology is proposed for restraining an amount of power consumption of a load.
Although greatly depending on the electric power circumstance in each country, a total electric power rate of a high-voltage receiver in Japan is determined by a basic rate and a power consumption rate, for example. The basic rate is determined, for example, on the basis of an integral power consumption (peak power demand) supplied from a grid in a predetermined period (for example, 30 minutes) in the past. On the other hand, the power consumption rate is determined on the basis of an amount of power to be consumed in a calculation target period. Therefore, it is preferable to control the amount of power consumption of each load so that the integral power consumption does not exceed a predetermined power consumption.
In this case, a technology is proposed which presents to a user an alarm indicating that the amount of power consumption should be restrained so that an integral power consumption of power supplied from a grid in a predetermined period does not exceed a predetermined power consumption. Specifically, on the basis of an amount of power supplied from a grid that increases for each unit time (hereinafter, a unit-time increased amount), an integral power consumption at the expiration timing of a predetermined period is predicted, and when the predicted integral power consumption exceeds a predetermined power consumption, an alarm indicating that the amount of power consumption should be restrained is presented to a user (for example, Patent Literature 1).
In the above-described technology, in order to acquire a breakdown of the integral power consumption, it may be considered to acquire amounts of power consumption of a plurality of loads connected to a grid. When the breakdown of the integral power consumption is acquired, it becomes possible to control the load so that the integral power consumption at the expiration timing of a predetermined period does not exceed a predetermined power consumption.
In such a case, it is necessary to acquire the amount of power consumption of a plurality of loads in a predetermined interval. Here, when a predetermined interval is shorter, a frequency of acquiring an amount of power consumption of a load increases, and power consumption necessary to acquire an amount of power consumption of a load (measure and report an amount of power consumption of a load) increases. On the other hand, when a predetermined interval is longer, the power consumption necessary to acquire an amount of power consumption of a load (measure and report an amount of power consumption of a load) decreases, and the frequency of acquiring the amount of power consumption of a load decreases.